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Howlett" , Vlastimil Babka , Jann Horn , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Zi Yan , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Pedro Falcato , Rik van Riel , Harry Yoo References: <20250627115510.3273675-1-david@redhat.com> <20250627115510.3273675-3-david@redhat.com> <1d98e96b-4bc9-45c1-9861-e0f3c5930ec2@redhat.com> <753a8900-d9ff-436c-8758-17d363967b30@lucifer.local> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: <753a8900-d9ff-436c-8758-17d363967b30@lucifer.local> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: qJiUooPR2Oo91_MDkoex-1gj07Mv1GsJ1UayCTmJh80_1751446852 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: E7DC44000F X-Stat-Signature: 4iwy6ukgqhj6njm4zpa7mm7awrqjrsy8 X-HE-Tag: 1751446854-819036 X-HE-Meta: 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 fHSJIK/A 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 02.07.25 10:51, Lorenzo Stoakes wrote: > On Wed, Jul 02, 2025 at 10:48:20AM +0200, David Hildenbrand wrote: >> On 02.07.25 10:42, Oscar Salvador wrote: >>> On Fri, Jun 27, 2025 at 01:55:08PM +0200, David Hildenbrand wrote: >>>> Let's clean up a bit: >>>> >>>> (1) No need for start_ptep vs. ptep anymore, we can simply use ptep >>>> >>>> (2) Let's switch to "unsigned int" for everything >>>> >>>> (3) We can simplify the code by leaving the pte unchanged after the >>>> pte_same() check. >>>> >>>> (4) Clarify that we should never exceed a single VMA; it indicates a >>>> problem in the caller. >>>> >>>> No functional change intended. >>>> >>>> Signed-off-by: David Hildenbrand >>> >>> Hi David :-), >>> >>> I have to confess that I fell in the same trap as Lorenzo wrt. >>> __pte_batch_clear_ignored changing the pte value. >>> So I'm not sure if it would be nice to place a little comment in >>> __pte_batch_clear_ignored claryfing that pte's value remains unchanged ? >> >> I mean, that's how all our pte modification functions work, really? :) >> >> Thanks! > > I mean, it might be that me and Oscar are similarly 'challenged' in this > respect :P (high 5 Oscar!) but I think the issue here is that it's sort of > a compounded use, and in fact some functions do modify stuff, which is why > we end up with all the ptep ptent etc. fun. > > Up to you re: comment, but I think maybe in cases where it's a reallly > compounded set of stuff it's potentially useful. > > But obviously we still do do this all over the place elsewhere with no > comment... Well, if you are not passing in a *value* and not a pointer to a function, you would not expect for that *value* to change? :) Yes, once we pass pointers it's different. Or when we're using weird macros. Adding a comment that a function will not modify a value that is ... passed-by-value? Maybe it's just me that doesn't get why that should be particularly helpful :) -- Cheers, David / dhildenb